Focal microwave-induced hyperthermia is being studied in an attempt to evaluate its utility in the management of glioblastoma multiforme. Studies consist of a) neuroradiobiological assays of thresholds of damage to normal brain following focal heating, b) dosimetric evaluation of heating efficacy, and c) engineering developments to improve the delivery and controllability of microwave-induced hyperthermia. Two methods of heating are being employed - one invasive and one non-invasive.